Not Charging after Madd bypass.

Typical alternator will charge up to 16v wide open but will normally self regulate via the functional voltage regulators limit of about 14.7v. The modern square back uses resistance to ground on one of the fields to regulate its output voltage. The points type regulators on the single field round backs uses duty cycle to average a 14.7v output over time, ie. an on and an off 12v 'excitation' duty cycle instead of a smooth regulation of power. If this theory helps In diagnostics....?